Packaging laminates generally comprise a substrate bearing one or more coating layers. The coating layers may, dependent upon their composition, be applied as molten plastics or may be applied wet, either in solution or as a dispersion in a carrier liquid, followed by drying. Until now, wet applied coatings have been applied singly with intermediate drying steps.
Wet coatings are also applied to substrates in the field of manufacturing photo papers. For this purpose, it is known to apply several wet layers simultaneously to a substrate using either a slide coater or a curtain coater.